Electrical appliances adapted to be powered by a standard AC voltage supplied to residences and businesses generally employ a dual conductor wire with each of the conductors covered by a rubber or plastic insulation. The wire is attached to the power input terminal of the appliance at one end and at the other end to a standard male plug having two parallel prongs adapted to be inserted into a standard female wall outlet connected to a power line. Various types of such plugs are known to the art. In one type the wire is inserted through an aperture in the rear of the plug and the insulation about the end of the wire is stripped away so that bare portions of the conductors can be affixed to two screws which are in electrical contact with the prongs of the plug. In another type of plug the wire is permanently attached to the prongs with the plug moulded around it during fabrication of the plug. The former type of plug requires a time-consuming effort in stripping the wires and attaching the stripped wires to the screws and is expensive to use in mass scale production. Moreover, consumers who wish to replace damaged plugs sometimes find it difficult to perform the necessary operations for attaching such plugs and/or lack the tools necessary to properly attach the plug to a wire. The permanently attached plug has the disadvantage that it cannot be re-used.
To overcome the problem associated with the foregoing type of connectors, plugs have been developed wherein a wire can be inserted through a plug housing and then pierced by projections on the plug prongs to achieve electrical contact without stripping the insulation from the wire. Such devices have, until now, been troublesome in that the prongs of the plug which must be separated from the plug housing to connect the wire tend to separate from the housing when the plug is withdrawn from an outlet in some instances. In other instances, the prongs are so strongly held within the housing that any attempt to remove them from the housing to re-use the plug may result in cracking of the housing and breaking or bending of the plug's conductors, thereby irreparably damaging the plug and requiring its replacement.